SAC Capital to Limit Cooperation on Probe

SAC Capital Advisors LP told clients it will no longer provide "unconditional" cooperation with a criminal insider-trading probe of the hedge-fund firm, marking an abrupt turn for a company that has spent months reassuring investors.

The move signals that a multiyear, multipronged government investigation of the company and its billionaire founder, Steven A. Cohen, has intensified, according to people familiar with the...